Power converter and pre-charging circuit of same

Abstract

A power converter configured to control an electrical load including a supply DC bus, a bus capacitor, a pre-charging circuit of the bus capacitor provided with a limiting resistor, a switched-mode power supply, and a starter assembly of the switched-mode power supply. The power converter includes a selection mechanism configured to connect the supply DC bus either, in a first state, to the starter assembly of the switched-mode power supply or, in a second state, to the bus capacitor to short circuit the limiting resistor.

The invention claimed is: 
     
       1. A power converter configured to control an electrical load, comprising:
 a DC power bus including a positive power line and a negative power line; 
 a bus capacitor; 
 a limiting resistor connected to the positive power line and to the bus capacitor, the bus capacitor being connected to the negative power line; 
 a switch mode power supply connected to the positive power line and to the negative power line; 
 a start-up assembly of the switch mode power supply connected to the negative power line of the DC power bus; 
 selection means configured to connect the positive power line, either, in a first state, to the start-up assembly of the switch mode power supply, or, in a second state, to the bus capacitor to short-circuit the limiting resistor; and 
 a control unit configured to control the selection means in the first state or in the second state. 
 
     
     
       2. The power converter as claimed in  claim 1 , wherein the start-up assembly of the switch mode power supply includes a start-up resistor and a capacitor connected in series, and a Zener diode connected in parallel with the capacitor. 
     
     
       3. The power converter as claimed in  claim 1 , further comprising a discharge resistor connected in parallel with the start-up assembly of the switch mode power supply.